George Anthony took the stand again today along with Casey's brother Lee to testify that police asked them to put certain questions to Casey during videotaped jailhouse interviews to circumvent the legal prohibition of questioning her when her lawyer wasn't present.
Lee Anthony testified that he was told by investigators, "We can't talk to her, but you can."
Statements by Casey Anthony that turned out to be false, like the existence of the babysitter, and her behavior during the investigation could be crucial to the case because there is very little direct evidence linking her to Caylee's murder.
Prosecutors appear to be building a case of circumstantial evidence and Anthony's statements and her behavior are going to be key to their attempts to win a conviction.
If the judge agrees that Anthony should have been read her rights sooner, the court could suppress all statements made by Anthony or suppress certain statements.
ABC News' Liz Sintay, Matt Knox and Lee Ferran contributed to this story.